DIN ViscometerViscoTester® 550

Flow Behavior

If the viscosity of a productdoes not only change withtemperature but also withstress, it is a non-Newtoniansubstance. There are materi-als that, due to their molecu-lar properties, show a lowerviscosity when subjected tostress (corresponds to theshearing in a rotationalviscometer). These arepseudoplastic liquids. On theother hand some materialsincrease their viscosity withstress (dilatant liquids) oreven react shear-time de-pendently. This shear-timedependent flow behavior isknown as thixotropy whenthe viscosity decreases withtime at constant shearingand as rheopexy when itincreases with time. Thisprocess has to be reversible,i.e. the viscosity will reachits original value againwithin a certain time whenthe shearing has stopped.

Yield Point

The yield point of a sub-stance corresponds to theforce that is necessary withinthe observation time to starta steady-state flow of thesubstance. According to thisdefinition, the yield pointscan be determined approxi-mately with a simple rota-tional viscometer. The flowbehavior with yield points iscommonly described as plas-ticity. A special case is theBingham flow behavior.

Introduction

Viscometry

The measuring techniquefor the determination of theviscosity of a liquid is calledviscometry. Viscosity is acharacteristic value thatdepends on environmentalconditions like e.g. tempera-ture and pressure.

Since it is a variable thatcan only be determined“indirectly”, the measuringresults are not “absolute” asthey rather depend on themeasuring method. Differ-ent instruments may deliverdifferent results and stillmeasure “correctly”, i.e. thetest substance should alsobe a factor when choosinga measuring instrument.

Viscometers

The Höppler falling ballviscometer C is the classicalinstrument for the measure-ment of the viscosity at de-fined environmental condi-tions. With the exceptionof this one instrument,ThermoHaake specializesin rotational viscometerslike instruments of theViscoTester 01/02 seriesor the ViscoTester 6/7.

The ViscoTester 550 bridgesthe gap between classicalQC viscosity measurementsand research rheometry. It issuitable for extensive investi-gations for quality control aswell as for routine measure-ments in the Research andDevelopment Department.Rheometers are instrumentsthat can also be used for thedetermination of elasticproperties (e.g. theThermoHaake RheoStressinstruments). These instru-ments are described in a sepa-rate brochure.

Viscosity curve ηηηηη = f (T)

Newtonian and non-Newtonian flow behavior

Bingham andplastic flow behavior

The ThermoHaake Viscometer-Program

Falling BallViscometer CVT 01/02, VT 6/7

ViscoTester550

RheoStress

γτ

γτ

T

η

τ°

Viscosity

Temperature

Shear Stress

Shear Stress

ShearRate

ShearRate

Yield Point

2

The ViscoTester 550 is a speed-controlledrotational viscometer that is driven by astep motor with up to 100 pre-definedspeeds of extreme accuracy.

From a table of 100 values, 10 valueseach can be selected within the range of0.5 to 800 min-1. The torque is measu-red via the deflection of a torsion ele-ment with a resolution of 1:1000 anddigitally displayed. The viscosity is cal-culated by a microprocessor from thetorque, speed and the geometry used.

The following measurements can beperformed either manually at the pushof a button, internally via programmedmethods or computer-controlled(special accessory at extra charge):● Automatic recording of flow curves● Time measurements● Temperature programs (with optional

circulator)● CD-method (preset deformation)

for the determination of a yield point

ViscoTester® 550

ViscoTester 550 with T/MV( T/MV as optional accessory)

Viscosity (mPas) PK5, 1° PK1, 1°Recommended range 100 - 10 000 500 - 100 000Max. range 5 - 100 000 50 - 1 000 000

Shear rate (1/s) 3 - 4800 3 - 4800

Shear stress (Pa) 0.6 - 612 3.48 - 3480Temperature (°C) -20 to 130 -20 to 130

Volume (cm3) 1.5 0.2

Cone angle (degrees) 1 1Max. particle size (mm) >100 >100

Technical data of the VT 550Number of speeds continuous

Speeds 0.5 – 800 min–1 / 0.1 steps

Temperature range -20 to 100°CTypical measuring time 2 to 3 minutes

Number of sensors 2 cups, 2 rotors

Reproducibility ± 1%Digital display yes

Interface RS232

Voltage/frequency 100 to 230 V/50 to 60 Hz

Viscosity (mPas) MV DIN SV DINRecommended range 20 - 10 000 100 - 100 000

Max. range 1 - 100 000 10 - 1 000 000

Shear rate (1/s) 0.65 - 1032 0.65 - 1032Shear stress (Pa) 0.1 - 120 0.7 - 740

Temperature (°C) -20 to 100 -20 to 100

Volume (cm3) 46 14Gap/max. particle (mm) 1.64/0.5 0.9/0.3

Measuring ranges cylinder-viscometers

Measuring ranges plate-cone viscometers

3

DIN/ISO-Viscometer 550 with Cylinder Measuring SystemOrder-No. 362-0021 European and 362-0022 US Version

Application

With this DIN/ISO viscometer and thecylinder measuring system, fluids frommany different fields of industry can becharacterized according to DIN53019/ISO 3219. Flow curves deliver a rheo-logical determination of Newtonianand non-Newtonian flow behavior.Application properties like sedimenta-tion, spreadability or running proper-ties of higher viscous products aredetermined by measuring the yieldpoint in the CD-mode.

Food IndustrySauces, mayonnaise, mustard, ketchupand raw materials like thickeningagents, stabilizers, starch or pectin

Cosmetic or Pharmaceutical IndustryCremes, lotions, shampoos, toothpastes and liquid soaps

Paint IndustryWater-based paints, latex paints, bondingagents, resins

Chemical IndustryLiquid and paste-like raw materials andintermediate products

Cylinder measuring systemDIN 53019/ISO 3219

These standardized measuring systemsare preferably used for the measurementof watery substances like watery latexpaints (DIN 53019), surfactants (DIN53214) and paints (DIN 53921). Theyeach consist of a measuring cup androtor that are used together with theThermoHaake temperature controlvessel. Characteristic values are stand-ardized in order to achieve comparablemeasuring results with different instru-ments. Further advantages are the easyhandling and cleaning as well as the lowmeasuring error with temperature pro-grams – all due to the geometrical form.

Contents of standard package:

● Viscotester 550 (115-230V/50-60Hz)● Support stand for the base unit● Temperature control vessel with

connector to circulator (Ø 8 mm)● PT100 temperature sensor● Measuring system MV DIN including:

Measuring cup MV DIN (steel 18/8)Rotor MV DIN (steel 18/8)

● Measuring system SV DIN including:Measuring cup SV DIN (steel 18/8)Rotor SV DIN (steel 18/8)

Wearing parts

Seal for measuring cup MV-DIN (10pcs.) order no. 222-1334

Features

● Viscosity measurements according toDIN 53019/ISO 3219

● Determination of the yield pointwith CD (preset deformation)

● Substances with small particles(<0.3 mm) can be measured

● Automatic flow curve recording withprogrammed procedures

● Print-out of the measuring results toa RS232 printer

● Interchangeable rotors for mediumand high viscous products

4

DIN/ISO-Viscometer 550 with Plate-Cone Measuring SystemOrder No. 362-5000 European and 362-5001 US Version

Application

With the cone-plate viscometer 550high viscous liquids and pastes frommany differing fields of industry can becharacterized according to ISO 3219.Flow curves deliver a rheological deter-mination of Newtonian and non-Newtonian behavior. Applicationproperties like spreadability or stabilityare determined by measuring the yieldpoint in the CD-mode.

Food IndustryDough, margarine, fats or butter

Cosmetic or Pharmaceutical IndustryCremes, soaps and lipstick

Paint and Electronic IndustryBonding agents, resins, ink, paste solder,solder stop paint, resistance pastes

Chemical IndustryPaste-like raw materials and intermediateproducts

Contents of Standard Package

● Viscotester 550 (115-230V/50-60Hz)● Support stand for base unit and

plate-cone measuring system● Cone and plate measuring system

PK200 with connector for circulator(Ø 8 mm)

● PT100 temperature sensor includedin the measuring plate

● Measuring system cone-plate:Measuring plate MP60 (Steel 18/8)Cone PK5, 1°Cone PK1, 1°

Cone and plate measuring system

The cone-plate measuring system ispreferably used for the measurementof firm, paste-like materials. It consistsof the lower measuring plate MP60 onwhich the interchangeable measuringcones (PK5, PK1) rotate thus shearingthe test sample. In ISO 3219 character-istic values are fixed in order to achievecomparable measuring results even ifinstruments are used that are not iden-tical. Further advantages are the easyhandling and cleaning.

Features

● Viscosity measurements accordingto ISO 3219

● Determination of the yield pointwith CD (preset deformation)

● Substances containing small particles(<0.1 mm) can be measured

● Automatic flow curve recordingwith programmed procedures

● Print-out of the measuring resultson RS232 printer

● Interchangeable cones

5

Measurement in Manual Mode

Select sensor:

Press

until the display shows

Press

until the desired sensor isdisplayed

Prog Prog

S.

➔➔

ThermoHaake VT 550

S. iD

StartStop0➔ ➔

➔

Prog ➔mPas °CPa x10001/s 1/min

Select display:

D

D

D

D

D

mPas

°C

1/min

1/s

Pa

S. i MV DIN

S. 2 SV DIN

S. 3i PK1,1°

S. 36 PK5,1°

Display:

Viscosity in [mPa.s]

Temperature in [°C]

Speed in [min-1]

Shear rate in [s-1]

Shear stress in [Pa]

Preset speed:

1.....10

mPas

Prog

➔

➔

D

Select speed program 1

(5 - 500 min-1) :

Select speed10 = 500 min-1

1 = 5 min-1

Result:

Read viscosity ηηηηη

ThermoHaake VT 550

8888D

StartStop0➔ ➔

➔

Prog ➔

mPas °CPa x10001/s 1/min

ThermoHaake VT 550

8. i0D

StartStop0➔ ➔

➔

Prog ➔

mPas °CPa x10001/s 1/min

6

Measurement:

Measurement in Automatic Mode

Select sensor:

P.0Select procedure 1 to 9

with

P.0 = normal mode

Prog ➔➔

ThermoHaake VT 550

P. 0D

StartStop0➔ ➔

➔

Prog ➔mPas °CPa x10001/s 1/min

The procedures 1 to 9 aredefined with the softwareOS550

ThermoHaake VT 550

P. iD

StartStop0➔ ➔

➔

Prog ➔

mPas °CPa x10001/s 1/min

ThermoHaake VT 550

P. 5D

StartStop0➔ ➔

➔

Prog ➔

mPas °CPa x10001/s 1/min

➔➔

P.iYield point determination

with CD mode

P.i or P.2

Prog ➔➔

P.5Recording of flow curve

Prog ➔➔

7

τ

t

= f(t)τ = f( ,t)

τ = f(γ)τ

t

τ0

ViscoTester, RotoVisco, RheoStress, RheoWin are registered trademarks of Thermo Haake. The product information in this document was correct at the time of printing, howeverspecifications are subject to alteration without notice due to the Thermo Haake philosophy of continual product innovation and development and any information containedherein should not be construed as a contractual commitment by Thermo Haake. All orders are accepted subject to our current Conditions of Sale, copies of which are availableon request. © Thermo Haake/Dec.2001 623-2039

A Thermo Electron business

InternationalThermo HaakeDieselstr. 476227 KarlsruheGermanyTel. +49(0)721 40 94-0Fax +49(0)721 40 94-300Hotline +49(0)18050 HAAKEinfo@thermohaake.comwww.thermohaake.com

USAThermo Haake5225 Verona RoadMadison, WI 53711Tel. 608-327-6777Fax 608-273-6827infousa@thermohaake.comwww.thermohaake.com

FranceThermo Rheo99 route de Versailles91160 ChamplanTel. +33(0)1 64 54 01 01Fax +33(0)1 64 54 01 87info@thermorheo.comwww.thermorheo.com

UKThermo PRISMEmerald WayStone Business Park, StoneStaffordshire ST15 0SRTel. +44(0)1785 813 648Fax +44(0)1785 814 633info@thermoprism.comwww.thermoprism.com